/* === CSS Custom Properties / Theming === */
:root {
    --bg-primary: #f5f5f5;
    --bg-secondary: #ffffff;
    --bg-toolbar: #ffffff;
    --bg-sidebar: #fafafa;
    --bg-hover: #e8e8e8;
    --bg-active: #d0d0d0;
    --text-primary: #333333;
    --text-secondary: #666666;
    --text-muted: #999999;
    --border-color: #ddd;
    --accent: #4a90d9;
    --accent-hover: #357abd;
    --canvas-bg: #ffffff;
    --grid-color: #e8e8e8;
    --grid-color-major: #d0d0d0;
    --shadow: 0 2px 8px rgba(0,0,0,0.1);
    --minimap-bg: rgba(255,255,255,0.95);
    --minimap-viewport: rgba(74,144,217,0.3);
    --context-bg: #ffffff;
    --selection-color: rgba(74,144,217,0.15);
}

[data-theme="dark"] {
    --bg-primary: #1e1e1e;
    --bg-secondary: #2d2d2d;
    --bg-toolbar: #2d2d2d;
    --bg-sidebar: #252525;
    --bg-hover: #3a3a3a;
    --bg-active: #4a4a4a;
    --text-primary: #e0e0e0;
    --text-secondary: #aaa;
    --text-muted: #777;
    --border-color: #444;
    --accent: #5a9fd9;
    --accent-hover: #7ab5e8;
    --canvas-bg: #ffffff;
    --grid-color: #2a2a2a;
    --grid-color-major: #333;
    --shadow: 0 2px 8px rgba(0,0,0,0.3);
    --minimap-bg: rgba(255,255,255,0.95);
    --minimap-viewport: rgba(90,159,217,0.3);
    --context-bg: #2d2d2d;
    --selection-color: rgba(90,159,217,0.15);
}

/* === Reset & Base === */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    overflow: hidden;
    height: 100vh;
    display: flex;
    flex-direction: column;
    user-select: none;
}

/* === Toolbar === */
#toolbar {
    display: flex;
    align-items: center;
    padding: 4px 8px;
    background: var(--bg-toolbar);
    border-bottom: 1px solid var(--border-color);
    gap: 4px;
    height: 40px;
    flex-shrink: 0;
    z-index: 100;
}

.toolbar-group {
    display: flex;
    align-items: center;
    gap: 2px;
}

.toolbar-separator {
    width: 1px;
    height: 24px;
    background: var(--border-color);
    margin: 0 4px;
}

.toolbar-spacer {
    flex: 1;
}

#toolbar button {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    border: none;
    background: transparent;
    color: var(--text-primary);
    border-radius: 4px;
    cursor: pointer;
    font-size: 11px;
    font-weight: 500;
    padding: 0;
}

#toolbar button:hover {
    background: var(--bg-hover);
}

#toolbar button.active {
    background: var(--accent);
    color: white;
}

#toolbar button:disabled {
    opacity: 0.35;
    cursor: default;
}

#toolbar button:disabled:hover {
    background: transparent;
}

#btn-export-png, #btn-export-svg, #btn-print {
    width: auto !important;
    padding: 0 10px !important;
    font-size: 11px !important;
}

#zoom-level {
    font-size: 11px;
    color: var(--text-secondary);
    min-width: 40px;
    text-align: center;
}

/* === App Container === */
#app-container {
    display: flex;
    flex: 1;
    overflow: hidden;
}

/* === Sidebar === */
#sidebar {
    width: 180px;
    background: var(--bg-sidebar);
    border-right: 1px solid var(--border-color);
    overflow-y: auto;
    flex-shrink: 0;
}

.sidebar-section {
    padding: 8px;
    border-bottom: 1px solid var(--border-color);
}

.sidebar-section h3 {
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    color: var(--text-muted);
    margin-bottom: 8px;
    letter-spacing: 0.5px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: space-between;
    user-select: none;
}

.sidebar-section h3::after {
    content: '';
    display: inline-block;
    width: 0;
    height: 0;
    border-left: 4px solid transparent;
    border-right: 4px solid transparent;
    border-top: 5px solid var(--text-muted);
    transition: transform 0.2s;
}

.sidebar-section.collapsed h3 {
    margin-bottom: 0;
}

.sidebar-section.collapsed h3::after {
    transform: rotate(-90deg);
}

.sidebar-section.collapsed > div {
    display: none !important;
}

#shape-palette, #network-palette, #org-palette, #engineering-palette, #connector-palette, #line-style-palette {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4px;
}

.palette-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 6px 4px;
    border: 1px solid transparent;
    border-radius: 4px;
    cursor: grab;
    transition: background 0.15s, border-color 0.15s;
}

.palette-item:hover {
    background: var(--bg-hover);
    border-color: var(--border-color);
}

.palette-item.active {
    background: var(--selection-color);
    border-color: var(--accent);
}

.palette-item svg {
    width: 48px;
    height: 32px;
    color: var(--text-primary);
    margin-bottom: 2px;
}

.palette-item span {
    font-size: 9px;
    color: var(--text-secondary);
    text-align: center;
}

.connector-type {
    cursor: pointer !important;
}

.line-style {
    cursor: pointer !important;
}

/* === Canvas === */
#canvas-container {
    flex: 1;
    position: relative;
    overflow: hidden;
    background: var(--canvas-bg);
}

#flowchart-canvas {
    position: absolute;
    top: 0;
    left: 0;
    cursor: default;
}

#flowchart-canvas.grabbing {
    cursor: grabbing;
}

#flowchart-canvas.crosshair {
    cursor: crosshair;
}

/* === Text Editor Overlay === */
#text-editor {
    position: absolute;
    border: 2px solid var(--accent);
    background: transparent;
    text-align: center;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    outline: none;
    resize: none;
    overflow: hidden;
    z-index: 50;
    padding: 4px;
}

/* === Minimap === */
#minimap-container {
    position: absolute;
    bottom: 12px;
    right: 12px;
    width: 180px;
    height: 120px;
    background: var(--minimap-bg);
    border: 2px solid #000000;
    border-radius: 4px;
    box-shadow: var(--shadow);
    overflow: hidden;
    z-index: 50;
}

#minimap-canvas {
    width: 100%;
    height: 100%;
}

#minimap-viewport {
    position: absolute;
    border: 2px solid var(--accent);
    background: var(--minimap-viewport);
    pointer-events: none;
}

/* === Properties Panel === */
#properties-panel {
    width: 200px;
    background: var(--bg-sidebar);
    border-left: 1px solid var(--border-color);
    overflow-y: auto;
    flex-shrink: 0;
    padding: 8px;
}

#properties-panel h3 {
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    color: var(--text-muted);
    margin-bottom: 12px;
    letter-spacing: 0.5px;
}

.props-hint {
    font-size: 12px;
    color: var(--text-muted);
    text-align: center;
    padding: 20px 0;
}

.prop-group {
    margin-bottom: 10px;
}

.prop-group label {
    display: block;
    font-size: 11px;
    color: var(--text-secondary);
    margin-bottom: 3px;
}

.prop-group input[type="text"],
.prop-group input[type="number"],
.prop-group select {
    width: 100%;
    padding: 4px 6px;
    border: 1px solid var(--border-color);
    border-radius: 3px;
    background: var(--bg-secondary);
    color: var(--text-primary);
    font-size: 12px;
    outline: none;
}

.prop-group input[type="text"]:focus,
.prop-group input[type="number"]:focus,
.prop-group select:focus {
    border-color: var(--accent);
}

.prop-group input[type="color"] {
    width: 100%;
    height: 28px;
    border: 1px solid var(--border-color);
    border-radius: 3px;
    cursor: pointer;
    padding: 2px;
    background: var(--bg-secondary);
}

.prop-group input[type="range"] {
    width: 100%;
    accent-color: var(--accent);
}

.prop-section {
    border: 1px solid var(--border-color);
    border-radius: 4px;
    padding: 6px;
    margin-bottom: 8px;
}

.prop-section-title {
    font-size: 9px;
    font-weight: 600;
    text-transform: uppercase;
    color: var(--text-muted);
    margin-bottom: 6px;
    letter-spacing: 0.5px;
}

.prop-row {
    display: flex;
    gap: 6px;
}

.prop-half {
    flex: 1;
    min-width: 0;
}

.prop-toggle-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.prop-toggle-row .toggle-label {
    font-size: 11px;
    color: var(--text-secondary);
    margin: 0;
}

.prop-toggle-row input[type="checkbox"] {
    accent-color: var(--accent);
    width: 16px;
    height: 16px;
    cursor: pointer;
}

.prop-actions {
    display: flex;
    gap: 4px;
    flex-wrap: wrap;
}

.prop-actions button {
    flex: 1;
    padding: 4px 6px;
    border: 1px solid var(--border-color);
    background: var(--bg-secondary);
    color: var(--text-primary);
    border-radius: 3px;
    cursor: pointer;
    font-size: 10px;
}

.prop-actions button:hover {
    background: var(--bg-hover);
}

/* === Context Menu === */
.context-menu {
    position: fixed;
    background: var(--context-bg);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    box-shadow: 0 4px 16px rgba(0,0,0,0.15);
    padding: 4px 0;
    min-width: 180px;
    z-index: 1000;
}

.context-item {
    padding: 6px 16px;
    font-size: 12px;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--text-primary);
}

.context-item:hover {
    background: var(--accent);
    color: white;
}

.context-item span {
    font-size: 10px;
    color: var(--text-muted);
    margin-left: 24px;
}

.context-item:hover span {
    color: rgba(255,255,255,0.7);
}

.context-separator {
    height: 1px;
    background: var(--border-color);
    margin: 4px 0;
}

/* === Scrollbar Styling === */
::-webkit-scrollbar {
    width: 6px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}

/* === Toolbar Select === */
#page-size-select {
    padding: 2px 4px;
    border: 1px solid var(--border-color);
    border-radius: 3px;
    background: var(--bg-secondary);
    color: var(--text-primary);
    font-size: 11px;
    outline: none;
    cursor: pointer;
    height: 28px;
}

#toolbar #btn-title-block {
    width: auto;
    padding: 0 8px;
    font-size: 10px;
    white-space: nowrap;
}

/* === Modal === */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.4);
    z-index: 2000;
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-content {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 20px;
    min-width: 320px;
    max-width: 400px;
    box-shadow: 0 8px 32px rgba(0,0,0,0.2);
}

.modal-content h3 {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 16px;
}

.modal-field {
    margin-bottom: 10px;
}

.modal-field label {
    display: block;
    font-size: 11px;
    color: var(--text-secondary);
    margin-bottom: 3px;
}

.modal-field input {
    width: 100%;
    padding: 6px 8px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    background: var(--bg-primary);
    color: var(--text-primary);
    font-size: 13px;
    outline: none;
}

.modal-field input:focus {
    border-color: var(--accent);
}

.modal-actions {
    display: flex;
    justify-content: flex-end;
    gap: 8px;
    margin-top: 16px;
}

.modal-actions button {
    padding: 6px 16px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    background: var(--bg-secondary);
    color: var(--text-primary);
    font-size: 12px;
    cursor: pointer;
}

.modal-actions button:hover {
    background: var(--bg-hover);
}

.modal-primary {
    background: var(--accent) !important;
    color: white !important;
    border-color: var(--accent) !important;
}

.modal-primary:hover {
    background: var(--accent-hover) !important;
}

/* === Help Modal === */
.modal-help {
    min-width: 680px;
    max-width: 780px;
    max-height: 85vh;
    display: flex;
    flex-direction: column;
    padding: 0;
}

.help-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 20px 12px;
    border-bottom: 1px solid var(--border-color);
}

.help-header h3 {
    margin: 0;
}

.help-close-btn {
    background: none;
    border: none;
    font-size: 22px;
    color: var(--text-muted);
    cursor: pointer;
    padding: 0 4px;
    line-height: 1;
}

.help-close-btn:hover {
    color: var(--text-primary);
}

.help-tabs {
    display: flex;
    gap: 0;
    padding: 0 12px;
    border-bottom: 1px solid var(--border-color);
    overflow-x: auto;
    flex-shrink: 0;
}

.help-tab {
    padding: 8px 10px;
    border: none;
    background: none;
    color: var(--text-muted);
    font-size: 11px;
    cursor: pointer;
    border-bottom: 2px solid transparent;
    white-space: nowrap;
    transition: color 0.15s, border-color 0.15s;
}

.help-tab:hover {
    color: var(--text-primary);
}

.help-tab.active {
    color: var(--accent);
    border-bottom-color: var(--accent);
    font-weight: 600;
}

.help-body {
    padding: 16px 20px;
    overflow-y: auto;
    flex: 1;
}

.help-content {
    display: none;
}

.help-content.active {
    display: block;
}

.help-content h4 {
    font-size: 13px;
    font-weight: 600;
    color: var(--text-primary);
    margin: 16px 0 8px;
}

.help-content h4:first-child {
    margin-top: 0;
}

.help-content p {
    font-size: 12px;
    color: var(--text-secondary);
    line-height: 1.5;
    margin-bottom: 8px;
}

.help-content ul, .help-content ol {
    font-size: 12px;
    color: var(--text-secondary);
    line-height: 1.6;
    padding-left: 20px;
    margin-bottom: 8px;
}

.help-content li {
    margin-bottom: 3px;
}

.help-content kbd {
    display: inline-block;
    padding: 1px 5px;
    font-size: 11px;
    font-family: monospace;
    background: var(--bg-hover);
    border: 1px solid var(--border-color);
    border-radius: 3px;
    color: var(--text-primary);
}

.help-content code {
    font-size: 11px;
    background: var(--bg-hover);
    padding: 1px 4px;
    border-radius: 2px;
    color: var(--accent);
}

.help-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 12px;
    margin-bottom: 12px;
}

.help-table td {
    padding: 5px 8px;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    vertical-align: top;
}

.help-table tr:nth-child(even) {
    background: var(--bg-primary);
}

.help-table td:first-child {
    white-space: nowrap;
    width: 35%;
}

.help-shortcuts td:first-child {
    width: 45%;
}

/* === Templates Modal === */
.modal-wide {
    min-width: 520px;
    max-width: 600px;
}

.modal-subtitle {
    font-size: 12px;
    color: var(--text-muted);
    margin-bottom: 14px;
}

.template-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8px;
    max-height: 400px;
    overflow-y: auto;
    margin-bottom: 8px;
}

.template-card {
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    cursor: pointer;
    transition: border-color 0.15s, background 0.15s, transform 0.1s;
    background: var(--bg-primary);
}

.template-card:hover {
    border-color: var(--accent);
    background: var(--selection-color);
    transform: translateY(-1px);
}

.template-card-name {
    font-size: 13px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.template-card-desc {
    font-size: 11px;
    color: var(--text-muted);
    line-height: 1.3;
}

/* === Print Styles === */
@media print {
    #toolbar, #sidebar, #properties-panel, #minimap-container, .context-menu {
        display: none !important;
    }
    #app-container {
        display: block;
    }
    #canvas-container {
        position: static;
        width: 100%;
        height: 100%;
    }
    body {
        background: white;
    }
}